The Creative Commons licenses enable copyright holders to grant some or all of their rights to the public while retaining others through a variety of licensing and contract schemes including dedication to the public domain or open content licensing terms. The intention is to avoid the problems current copyright laws create for the sharing of information.
The project provides several free licenses that copyright owners can use when releasing their works on the Web. It also provides RDF/XML metadata that describes the license and the work, making it easier to automatically process and locate licensed works. Creative Commons also provides a "Founders’ Copyright" contract, intended to re-create the effects of the original U.S. Copyright created by the founders of the U.S. Constitution.
All these efforts, and more, are done to counter the effects of what Creative Commons considers to be a dominant and increasingly restrictive permission culture. In the words of Lawrence Lessig, founder of Creative Commons and former Chairman of the Board, it is "a culture in which creators get to create only with the permission of the powerful, or of creators from the past". Lessig maintains that modern culture is dominated by traditional content distributors in order to maintain and strengthen their monopolies on cultural products such as popular music and popular cinema, and that Creative Commons can provide alternatives to these restrictions.
For more info goto http://en.wikipedia.org/wiki/Creative_Commons